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Related papers: Semisimplification of contragredient Lie algebras

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We show how various constructions of $\mathbb{Z}$-graded Lie superalgebras are related to each other. These Lie superalgebras have a Lie algebra $\mathfrak{g}$ as the subalgebra at degree 0, an odd $\mathfrak{g}$-module V as the subspace at…

Representation Theory · Mathematics 2026-02-24 Sylvain Lavau , Jakob Palmkvist

In the framework of algebraic supergeometry, we give a construction of the scheme-theoretic supergeometric analogue of Chevalley groups, namely affine algebraic supergroups associated to simple Lie superalgebras of classical type. In…

Rings and Algebras · Mathematics 2012-09-04 R. Fioresi , F. Gavarini

We say that a finite dimensional Lie algebra is quasi-reductive if it has a linear form whose stabilizer for the coadjoint representation, modulo the center, is a reductive Lie algebra with a center consisting of semisimple elements.…

Representation Theory · Mathematics 2011-10-14 Karin Baur , Anne Moreau

The main purpose of this work is to develop the basic notions of the Lie theory for commutative algebras. We introduce a class of $\mathbbZ_2$-graded commutative but not associative algebras that we call ``Lie antialgebras''. These algebras…

Mathematical Physics · Physics 2010-10-18 Valentin Ovsienko

We construct certain integral structures for the cores of reduced tame extended affine Lie algebras of rank at least 2. One of the main tools to achieve this is a generalization of Chevalley automorphisms in the context of extended affine…

Quantum Algebra · Mathematics 2021-06-22 Saeid Azam , Amir Farahmand Parsa , Mehdi Izadi Farhadi

We consider a proper parabolic subalgebra p of a simple Lie algebra g and the Inonu-Wigner contraction of p with respect to its decomposition into its standard Levi factor and its nilpotent radical : this is the Lie algebra which is…

Representation Theory · Mathematics 2025-04-25 Florence Fauquant-Millet

A new class of integrable mappings and chains is introduced. Corresponding $(1+2)$ integrable systems invariant with respect to such discrete transformations are presented in an explicit form. Their soliton-type solutions are constructed in…

Mathematical Physics · Physics 2007-05-23 A. N. Leznov

We overview classifications of simple infinite-dimensional complex $\mathbb{Z}$-graded Lie (super)algebras of polynomial growth, and their deformations. A subset of such Lie (super)algebras consist of vectorial Lie (super)algebras whose…

Representation Theory · Mathematics 2024-06-25 Dimitry Leites , Irina Shchepochkina

Loday's dendriform algebras and its siblings pre-Lie and zinbiel have received attention over the past two decades. In recent literature, there has been interest in a generalization of these types of algebra in which each individual…

Rings and Algebras · Mathematics 2020-07-14 Marcelo Aguiar

We introduce a remarkable subset "the stem" of the set of positive roots of a reduced root system. The stem determines several interesting decompositions of the corresponding reductive Lie algebra. It gives also a nice simple three…

Differential Geometry · Mathematics 2015-03-17 George Dimitrov , Vasil Tsanov

We introduce 3-irreducible modules, even roots and odd roots for Leibniz algebras, produce a basis for a root space of a Leibniz algebra with a semisimple Lie factor, and classify finite dimensional simple Leibniz algebras with Lie factor…

Rings and Algebras · Mathematics 2007-05-23 Keqin Liu

We suggest a (conjectural) construction of a basis in the plus part of the affine Lie algebra of type ADE indexed by irreducible components of certain quiver varieties. This construction is closely related to a string-theoretic construction…

Mathematical Physics · Physics 2007-05-23 Igor Frenkel , Anton Malkin , Maxim Vybornov

A Lie algebra $L$ is said to be $(\Theta_{n},sl_{n})$-graded if it contains a simple subalgebra $\mathfrak{g}$ isomorphic to $sl_{n}$ such that the $\mathfrak{g}$-module $L$ decomposes into copies of the adjoint module, the trivial module,…

Rings and Algebras · Mathematics 2021-04-21 Alexander Baranov , Hogir M. Yaseen

We show that a fundamental sandwich algebra has an analogue of a root system of a semisimple Lie algebra. This leads to an analogue of a Weyl group, which we study in another paper.

Rings and Algebras · Mathematics 2022-08-04 Richard Cushman

Levi's theorem decomposes any arbitrary Lie algebra over a field of characteristic zero, as a direct sum of a semisimple Lie algebra (named Levi factor) and its solvable radical. Given a solvable Lie algebra $R$, a semisimple Lie algebra…

Representation Theory · Mathematics 2013-02-19 Pilar Benito , Daniel de-la-Concepción

We investigate the structure and representation theory of finite-dimensional $\mathbb{Z}$-graded Lie algebras, including the corresponding root systems and Verma, irreducible, and Harish-Chandra modules. This extends the familiar theory for…

Representation Theory · Mathematics 2025-07-02 Mark D. Gould , Phillip S. Isaac , Ian Marquette , Jorgen Rasmussen

We consider a fixed block for the equivariant perverse sheaves with nilpotent support in the $1$-graded ccomponent of a semisimple cyclically graded Lie algebra. We give a combinatorial parametrization of the simple objects in that block.

Representation Theory · Mathematics 2016-10-03 George Lusztig , Zhiwei Yun

There are several researches on Lie algebras and Lie superalgebras graded by finite root systems. In this paper, we study Leibniz algebras graded by finite root systems and obtain some results in simply-laced cases.

Representation Theory · Mathematics 2010-06-30 Dong Liu , Naihong Hu

This paper is a continuation of [5]. Using the root categories, we define the compact real forms of the complex semisimple Lie algebras, and maximal compact subgroups of the Chevalley groups over $\mathbb{C}$. In [7], Lusztig used the…

Representation Theory · Mathematics 2026-02-26 Buyan Li , Jie Xiao

Decomposition classes provide a way of partitioning the Lie algebras of an algebraic group into equivalence classes based on the Jordan decomposition. In this paper, we investigate the decomposition classes of the Lie algebras of connected…

Representation Theory · Mathematics 2025-11-04 Joel Summerfield